Although efficacy of therapeutic treatments is dependent upon the mechanism of action of the agent used, other factors can also be important for eliciting an optimal response. For example, dosage and timing of administration relative to onset of disease as well as a number of complex issues involving pharmacokinetic and pharmacodynamic characteristics can be important considerations.
Over the years a variety of studies have been carried out with an array of therapeutic agents in an effort to establish optimal strategies for drug delivery. Drug regimens for many different types of diseases have evolved into combination therapies. For example, in some instances, combinations are used to improve efficacy by (1) combining drugs that have the same or different disease targets; (2) combining two drugs where the activity of the two in combination is greater than the sum of the activities of each alone; and (3) a combination of two drugs wherein one drugs one acts directly on the disease state, while the other improves the subject's symptoms indirectly. However, such disparate drugs with disparate roles in disease treatment often differ dramatically with respect to chemical nature, and drug delivery issues in combination therapy can be very challenging.
Therefore, it is an object of the invention to provide compositions and methods for improved drug delivery and disease treatment.
It is another object of the invention to provide compositions and methods for improving delivery and efficacy of an active agent to a target cell.
It is a further object of the invention to provide compositions and methods for improving delivery and efficacy of combination therapies including at least two active agents.
It is yet a further object of the invention to provide specific combination therapies to induce or enhance an immune stimulatory response in a subject in need thereof.